Fish oil supplementation with and without added vitamin E differentially modulates plasma antioxidant concentrations in healthy women

The purpose of this study was to assess the effect of fish oil with or with out vitamin E on plasma vitamin antioxidants. Thirty-three apparently healt hy women aged 18-28 yr were recruited from the university environs, and 30 completed the double-blinded, parallel design supplementation trial. Blood samples were collected at baseline (week 0) and following 28 d of supplemen tation with three capsules/d (0.8 g x 3) of either fish oil (FO) or FO with vitamin E (3 IU/g) (FOE). An additional blood sample was taken at day 91 ( washout). Plasma antioxidant vitamins, fatty acid composition, and lipid pe roxides were measured. Plasma alpha-tocopherol concentrations were increase d significantly in both groups postsupplementation FO (P = 0.018) and FOE ( P = 0.003) compared with baseline and washout values. Plasma retinol concen tration was significantly increased (P = 0.034) compared with baseline and washout values following supplementation with FOE but not FO, while plasma beta-carotene was significantly increased (P = 0.036), compared with baseli ne and washout values, following supplementation with FO but not FOE. There was a trend (P = 0.059) toward decreased plasma ascorbic acid following FO supplementation compared with baseline and washout. Plasma lipid peroxides did not change following either supplementation. Results suggest that low- dose FO feeding with and without vitamin E differentially modulates plasma antioxidant vitamins but has no significant effect on lipid peroxidation.